Corals from 3 meters and 65 meters were studied and compared for their responses to light. Corals were also transplanted from extremely low light to surface conditions, and vis versa to study the effects of light change and adaptability.

Mesophotic light levels are between 5 and 100 µmol…..or about 250-5,000 lux. Basically up to the light compensation point of many critters. Above that level and “normal” photosynthesis processes kick in.